Online Exclusives

AJRR Publishes Annual Report on Hip and Knee Replacements

By American Joint Replacement Registry | November 24, 2015

Report analyzes 82,841 hip arthroplasties and 128,880 knee arthroplasties from 2012-2014.

Orthopedic surgeons and device manufacturers around the United States have always wondered what common trends existed between hip and knee replacement patients. Whether it’s the most common material for implants or the underlying reasons patients are seeking surgery, the orthopedic field has been continuously searching for significant, reliable data to shed light on these important issues. Luckily, the American Joint Replacement Registry (AJRR) recently released an annual report that covers a wide range of topics related to hip and knee replacements.

The 2014 Annual Report on Hip and Knee Arthroplasty Data contains data from 236 participating hospitals representing 45 states. In the report, 82,841 hip arthroplasties and 128,880 knee arthroplasties from 2012-2014 are analyzed. These surgeries were performed by more than 2,200 surgeons that come from hospitals of varying sizes. Based on bed count, 30.9 percent of participating hospitals were large (over 400 beds), 48 percent were medium (100-399 beds), and 21.1 percent were small (1-99 beds). The hospitals also differed by teaching affiliation; 21 percent were major teaching, 35.6 percent were minor teaching, and 43.3 percent were non-teaching hospitals.

“The number of procedures in the registry grew by 164 percent since our first formal report last year,” said Daniel J. Berry, MD, chair of the AJRR board of directors. “Our first report covered 80,227 procedures and this one covers the collection and analysis of 211,721 procedures related to hip and knee replacements that have taken place from when we began collecting data up until December 2014.”

The AJRR data has led to several fascinating findings. The 2014 Annual Report reveals that the leading reason for hip and knee replacement is osteoarthritis. Also, out of the surgeries studied, 59.7 percent of females received total joint replacements as opposed to 40.3 percent of males.

Many orthopedists are interested in finding out what creates the need for hip and knee arthroplasty revisions. The leading cause of arthroplasty revisions varied based on whether they were early or not. For both early hip and early knee revisions, infection was a leading cause. However, in early total hip arthroplasties, dislocation was leading cause of revision too. Primary total hip and knee arthroplasty revisions both had loosening as a leading cause, but total hip arthroplasty revisions had an additional leading cause: dislocation.

Device manufacturers have much to gain from examining the data contained in the registry as well. In 2014, there was a huge increase in the use of ceramic heads in total hip arthroplasties. Ceramic heads may be skewed toward being used for younger patients, but almost half of all total hip arthroplasties use ceramic heads currently. To put things into perspective, the average age of patients in the AJRR data is 66.5 years old. In regard to total knee arthroplasties, about one third of patients were given cross-linked polyethylene implants. Patellar resurfacing is very popular in the United States, and at least 80 percent of total knee arthroplasties in the AJRR had patellar replacement.

The annual report also included a section on AJRR’s achievements from the previous year. High on the list among these is the launch of the Level II data collection pilot program. Level II data includes patient co-morbidities and complications. AJRR solicited 20 volunteers from their participating hospitals to submit Level II data whenever it was possible. 8,126 procedures were submitted by the program’s end. The timing of postoperative complications capturing was an issue, so AJRR will work to improve it with consistent reporting and clearly defined data element definitions in the future.

AJRR has come a long way since the data presented in the 2014 Annual Report was released. The National Registry now has nearly 600 participating hospitals, institutions from all 50 states, and over 350,000 total procedures. AJRR can now accept Level III patient-reported outcomes data from participants. Additionally, AJRR released a separate California Joint Replacement Registry (CJRR) Annual Report. AJRR and CJRR merged in March of 2015, and the CJRR Annual Report addresses the scientific assessment of devices, treatment protocols, surgical approaches, and patient factors influencing the results of hip and knee replacement surgeries for the state of California.

“With the continued support of the diverse stakeholders in the orthopedic community, AJRR will keep on growing and will reach its goal of collecting over 90 percent of all hip and knee replacement procedures performed in the U.S.,” said Dr. Berry. “We are thankful to the hospitals and surgeons who recognize the importance of a registry by entering their surgical data into the AJRR. We will continue our diligence in building a valuable national hip and knee arthroplasty registry that has a positive impact on patient care and the quality and durability of joint replacement surgery in the United States.”

For a downloadable copy of the 2014 Annual Report, visit

Related News:

Related Markets:

  • Loading Orthopedic Devices with Biologics and Pharmaceuticals

    Loading Orthopedic Devices with Biologics and Pharmaceuticals

    Dr. Kevin Nelson, Founder and CSO, TissueGen Inc.||May 19, 2017
    Fiber technology enables the delivery of the therapeutic components via a biodegradable platform that can be implanted.

  • Looking Beneath the Surface

    Looking Beneath the Surface

    Sam Brusco, Associate Editor||May 19, 2017
    Surface treatments seek to improve orthopedic device usability, longevity, and bone integration.

  • Going to Extremes

    Going to Extremes

    Michael Barbella, Managing Editor||May 19, 2017
    The innovation and market value found in extremity solutions is prompting a change of heart among major orthopedic firms.